Tony Heald / Red-Billed Teal (Anas erythrorhyncha) foraging in water. Etosha National Park, Namibia, January.

Vincent Grafhorst / Cape Teal (Anas capensis) standing in shallow water, Gaborone Game Reserve, Botswana

Alan Williams / Common teal (Anas crecca) male displaying, Martin Mere WWT, Lancashire, UK, February

Andrew Parkinson / Male Common teal (Anas crecca) swimming towards the photographer, Norfolk, UK, January

Andrew Parkinson / Common teal (Anas crecca) profile of a male with his head feathers erect, Norfolk, UK, January

Gabriel Rojo / Silver teal taking off {Anas versicolor} La Pampa, Argentina

Rolf Nussbaumer / Common teal {Anas crecca} male preening, Switzerland.

David Tipling / Common teal {Anas crecca} male duck, UK

Mike Potts / New Zealand scaup (Aythya novaeseelandiae) on Lake Wanaka, South Island, New Zealand.

Mike Read / Eurasian wigeon (Anas penelope), Common teal (Anas crecca) and Northern shoveler (Anas clypeata) flock in flight. Greylake Nature Reserve, near Othery, Somerset Levels, England, UK. February.

Mike Read / Common teal (Anas crecca) pair calling. Greylake Nature Reserve, near Othery, Somerset Levels, England, UK. February.

Mike Read / Common teal (Anas crecca) and Eurasian wigeon (Anas penelope) flock in flight. Greylake Nature Reserve, near Othery, Somerset, England, UK. February.